Waveguide structure and printed-circuit board

摘要

A waveguide structure or a printed-circuit board is formed using a plurality of unit structures which are repetitively aligned in a one-dimensional manner or in a two-dimensional manner. The unit structure includes first and second conductive planes which are disposed in parallel with each other, a transmission line having an open end which is formed in a layer different from the first and second conductive planes and positioned to face the second conductive plane, and a conductive via electrically connecting the transmission line to the first conductive plane.

主权项

1. A waveguide structure comprising:
a first conductive plane; a second conductive plane continuously laid in parallel with the first conductive plane; and a plurality of unit structures, each of which includes:
a transmission line having an open end, which is formed in a different layer from the first conductive plane and the second conductive plane and is positioned to face the second conductive plane; anda conductive via electrically connecting the transmission line to the first conductive plane, wherein the unit structures are repetitively aligned in a one-dimensional manner or in a two-dimensional manner, and wherein the waveguide structure is configured to suppress electromagnetic propagation between a power source and a ground plane at a frequency f satisfying an inequality Im(Y(f))≦0, where Im(Y(f)) is an imaginary component of a parallel admittance Y(f) defined as:Y⁡(f)=1i⁡(2⁢π⁢⁢fLvia-Z0tan⁡(2⁢π⁢⁢f⁢ɛeff⁢ɛ0⁢μ0⁢d))+i⁢⁢2⁢π⁢⁢fCplane where f denotes frequency, i denotes an imaginary component meaning that i2=−1, Lvia denotes an inductance of the conductive via, Cplane denotes a capacitance between the power source and the ground plane, Z0 denotes a characteristic impedance of the transmission line, d denotes a length of the transmission line, ∈eff denotes an effective dielectric constant, ∈0 denotes a dielectric constant under vacuum, and μ0 denotes a magnetic permeability under vacuum.